Dorico 5 will not install

I bought my Dorico 4 as a crossgrade from Sibelius. Does this entitle me to say that because I am runnung the full version of Dorico 4, that I am entitled to buy Dorico 5 as an update from Dorico 4
I went ahead and purchased Pro 5 this morning and now IO cannot open either Dorico 4 or Dorico 5

Sorry for the typos!
I think the trouble is that I have two different My Steinberg identities into which I can actually log in
In one of theses no products are listed whilst in the more recent log in I can see Dorico 5 as a Steinberg licenced product and Cubase 8 is listed under elicenced products.
When I bought the upgrade from D3 to D5 this morning I believe now that I gave as My Steinberg login the wrong email address.
I suspect that the fact that I bought D4 Pro as a crossgrade from Sibelius is irrelevant here. I would appreciate some assistance from the moderators of this forum.

Hi @Julian_C. Is the problem that you’ve got two Steinberg IDs and you have different product split across them? If you want to send me a private message with the two Steinberg IDs in question, I’d be happy to ask our support team to help you.